1. Field of the Invention
The present invention relates to a plate-link chain made of a large number of plates that form plate sets, where adjacent plate sets are hingedly connected to each other by pairs of rocker members. The rocker members of a rocker member pair have rolling surfaces that bear against each other. Some plate sets, preferably every second one, have a cover plate on their outwardly-facing sides, and the two rocker members associated with the plate set provided with the cover plates are received in receiving openings of the cover plates. The present invention also relates to a cover plate for such a plate-link chain.
2. Description of the Related Art
One form of plate-link chain of this type is known from International Publication No. WO 2006/133667. That publication discloses a plate-link chain in which the rocker members are firmly connected to guide plates, wherein the guide plates receive the rocker members and have receiving openings that have two relief cuts. A plate-link chain, in particular a toothed plate-link chain, normally includes toothed plates as well as cover plates, and short and long rocker members. The varying number of toothed plates in the plate links results in a non-uniform distribution of stiffness in the chain strand. The stiffness of the cover plates serves to balance that difference in stiffness. The cover plate also has the function of lateral guidance for the plate-link chain. The long rocker members are pressed into corresponding openings in the cover plates. The compression connection must absorb the forces that arise because of the lateral guidance function. In the opening of the cover plate for receiving the rocker members there are two regions with especially small radii, at which critical stresses occur. From the disclosure in WO 2006/133667 it is known to use relief cuts at those two places in order to reduce the critical stresses.
The relief cuts in accordance with the existing art reduce the peak stresses that occur. In certain cases the peak stresses that occur can nevertheless be higher than desired. An object of the present invention is therefore to further reduce the stresses that occur in the cover plate when it is under load.